Creative Upcycling of Wood Waste into Furniture: Bridging Durability Testing and Economic Viability, a Case Study

In this article, static durability testing is combined with an economic analysis of selected furniture manufactured from solid oak residues. Durability was assessed under the EN 1728 and EN 12520 static-load procedures, and dimensional stability was examined using statistical process-control tools (normality analysis, kurtosis and Shewhart control charts). Chairs intended for children were tested for the body mass of five-, seven- and nine-year-old children, as well as for an adult (seat force F1 = 250–850 N, backrest force F2 = 90–290 N). The tested chairs met the strength and durability requirements of the applied standards, and none overturned or tended to tip. A manufacturing cost and profitability analysis then quantified the cost structure. Material accounted for only 10–31% of manufacturing costs, with labour as the dominant component, reflecting the labour intensity of upcycling irregular residues into individually designed furniture. Manufacturing costs per item ranged from PLN 108 to PLN 251 against trial sale prices of PLN 250 to PLN 1300, yielding net profit margins of 46–81%. The findings indicate that upcycling post-production residues can improve the economic and potential environmental performance of furniture enterprises and support circular-economy objectives by reducing demand for virgin timber.